Upgraded Linux to 64bit Mint 20 (XFCE) based on Ubuntu 'Focal.'
Crossover installed without any issues and my previous FL bottles seem to run okay.
Tested the FL 20 CrossTie to install FL Studio 20.7.1 into a new bottle, choosing all the defaults (Download the installer, Win7-32 Bottle, - but: deselect asio-for-all). Everything installed and runs as expected.
Installed again into an older bottle (with all my VST's and add-ons, migrating settings) to upgrade my "Working Version" to FL 20.7.1. Again, everything seems to work as expected.